Melt the chocolate. To use the microwave method, place chocolate in a bowl and stir between 30 second intervals until it's melted. I used the double boiler method to melt the milk chocolate (place a Pyrex bowl filled with the chocolate in a saucepan filled with water that doesn't quite touch the bottom of the bowl, stir periodically until the chocolate's melted). I melted the white chocolate chips and dark chocolate chips in the microwave, placing each in a small bowl.
Use a spatula to spread the milk chocolate evenly on the parchment paper. I avoided the corners of the baking sheet. Drizzle the melted white and dark chocolate onto the milk chocolate using small spoons (just drizzle and fling it haphazardly). I took turns with the white and dark chocolate so they'd overlap more evenly.
Sprinkle the toppings over the chocolate and refrigerate for at least an hour. Once it has set, use your hands to break it up into various size pieces. Store in the fridge or another cool area so it doesn't melt.
Recipe is easily doubled (just use two baking sheets). You can adjust the quantities of toppings as needed; I started with 1/4 cup of each topping and I ended up with a bunch left over.